Sample introducing system for use in liquid chromatography

ABSTRACT

A sample introducing system for use in liquid chromatography, wherein samples stored in a plurality of sample reservoirs are each intermittently transferred to a sample reserving means, and every time when a sample has been transferred to the sample reserving means, an eluting or developing solution is fed through the sample reserving means to a separating column thereby to introduce the sample to the separating column. In addition, a development suppressing liquid can be fed to the separating column prior to each introduction of the sample to the separating column.

Cl ill Tl ted States Patent [111 3,575,295

[72] Inventors KasumiYoshida [50] Field of Search 210/31, Mit-shi; 198; 73/231; 55/67, 197, 386 Takehide Satou; Masato Matsushima; Yoshio Fujii, Katsuta-shi, Japan i 1 References C t d 2 5 9 1969 UNITED STATES PATENTS 1e pr. Patented p b, 1971 3,373,872 3/1968 Hrdma 2l0/l98 [73] Assignee Hitachi, Ltd. Primary Examiner-LLDeCesare Tokyo, Japan v Attorney-Craig and Antonelli [32] Priority Apr. 11, 1968, Dec. 9, 1968, Jan. 22, 1969 [33] Japan [31] R4485, 43/89542 and 44/4117 ABSTRACT: A sample introducing system for use in liquid chromatography, whereln samples stored in a plurality of sample reservoirs are each intermittently transferred to a sample reserving means, and every time when a sample has been transferred to the sample reserving means, an eluting or [54] EM FOR USE IN developing solution is fed through the sample reserving means 16 Cl im 60 toaseparating column thereby to introduce the sample to the a rawmg separating column. In addition, a development suppressing [52] US. Cl 210/198 liquid can be fed to the separating column prior to each [51} Int. Cl B0ld /08 introduction of the sample to the separating column.

23 9 26 2/ 29 50 l a L on o I I 42 2 E2. ,i rm I l 3 l 4 zii 4i M lmmfili [II x 36 PATENTFU APR20 I971 SHEET 3 0F 4 K INVENTORS RSO d n? 5 a 44. S945 sud); yes/7,6 [13 m BY MMQWM ATTORNEYS SAMPLE llNTlitODUCiNG SYSTEM FOR USE 1N L1QlJllD CHROMATOGRAPHY BACKGROUND OF THE INVENTION 1. Field of the invention This invention relates to a sample introducing system for use in liquid chromatography, and especially to a sample introducing system which can introduce a plurality of samples intermittently in succession to a sample separating means for liquid chromatography.

2. Description of the Prior Art in former times, the time required for the analysis of a sample by liquid chromatography was much longer than the time required for introducing the sample to a sample separating means, and therefore, it was not necessary to speciallyshorten the time required for introducing samples. However, as the results of the shortening of the analyzing time accomplished in recent years, the ratio of the time consumed in the process of introducing samples to the separating means to the whole analyzing time has been so increased that the shortening of the time of the sample introducing process as well as the automating of the sample introducing process including sampling and sample measuring processes have suddenly come to he noticed with great interest.

SUMMARY OF THE INVENTION Accordingly, an object of this invention is to provide a sample introducing system for use in liquid chromatogaphy which can introduce a plurality of samples intermittently in succession to a sample separating means.

Another object of this invention is to provide a sample introducing system for use in liquid chromatography which is useful for shortening the time required for the sample introducing process.

Still another object of this invention is to provide a sample introducing system for use in liquid chromatography which can always introduce a constant amount of sample so that good reproducibility of the results of separation is obtained.

Still another object of this invention is to provide a sample introducing system for use in liquid chromatography, wherein the sample reservoirs are free from the action of a high pressure in the sample separating means.

Still another object of this invention is to provide a sample introducing system for use in liquid chromatography having improved performance of separation.

Still another object of this invention is to provide a sample introducing system for use in liquid chromatography wherein the contamination of samples by each preceding sample, which causes errors of the results of separation, is prevented.

Still another object of this invention is to provide a sample introducing system for use in liquid chromatography having a plurality of separating columns to which samples are introduced intermittently in succession. v

According to this invention, a sample introducing system for use in liquid chromatography is provided, which comprises sample separating means, an eluting solution source, means for feeding the eluting solution from said source to said sample separating means, sample reservoir supporting means carrying a plurality of sample reservoirs, sample reserving means, sample drawing means adapted to be intermittently actuated to transfer a sample in one of said sample reservoirs to said sample reserving means, and changeover means adapted to be intermittently actuated to feed the eluting solution to said sample separating means through said sample reserving means thereby to intennittently introduce the sample reserved in said sample reserving means to said sample separating means and at the same time to intercept the communication between said sample reserving means and said sample reservoir supporting means.

The above-mentioned objects and features of this invention will become more apparent from the following description of some preferred embodiments of this invention made with reference to the accompanying drawings.

BRIEF DESCRlPTlON OF THE DRAWlNG In the drawing,

FIG. 1 is a diagrammatic view of an embodiment of the sample introducing system for use in liquid chromatography according to this invention, wherein the sample reservoir supporting means is shown in the section taken along line l-O-l in H0. 2;

FIG. 2 is a partly plan and partly sectional view of the sample reservoir supporting means in FIG. 1, the section being taken along line [H1 in FIG. 1;

FIG. 3 is a diagrammatic view of another embodiment of the sample introducing system for use in liquid chromatography according to this invention;

FIG. 4 is a diagrammatic plan view of the sample reservoir supporting means in FIG. 3; and

H08. 5 and 6 are diagrammatic views of other embodiments of the sample introducing system for use in liquid chromatography according to this invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1 and 2, there is shown an embodiment of the sample introducing system of this invention for use in liquid chromatography, wherein it includes a separating column 1, eluting or developing solution source 2, cleaning liquid source 3, flow changeover means 4, sample drawing means 5 and sample reserving means 6. The flow changeover means 4 comprises a changeover cam 50 drivingly connected with a driving means 7, a cylinder 16 provided with eight port openings 8, 9, 10, ll, l2, 13, 14 and 15 and a piston 29 inserted in the cylinder 16 and adapted to slide therealong through six O-rings 22, 23, 24, 25, 26 and 27 which are carried by the piston 29 at determined axial positions therealong and are fluidtightly in contact with the bore of the cylinder 16, whereby five annular passages 17, 18, 19, 20 and 21 are defined. The piston 29 is resiliently urged toward right seen in FIG. 1 by a compression spring 28, while the right end of the piston is controllingly abutted by the cam surface of the changeover cam 50.

The sample drawing means 5 comprises a cylinder 31 and a piston 32 cooperating with the cylinder, wherein the piston 32 having a piston rod 33 is laid under the control of a cam 30 carried on the same shaft as the cam 51] under the cooperation of a compression spring 34 so that the piston 32 of the sample drawing means 5 is reciprocated in synchronism with the changing-over of the changeover means 4.

With respect to the eight ports of the cylinder 16, the port 8 is connected with the cleaning liquid source 3, the port 9 with the inlet end of the separating column 1, the port 10 with the eluting solution source 2 through a pump 35, the port 11 with the cylinder 31 of the sample drawing means 5, the port 12 with a sample reservoir supporting means 45 which will be explained later, the port 13 with the port 14 through the sample reserving means 6 which may be a tube made of e.g. Teflon of a suitable length as described later, and the port 15 with an exhaust pipe. The changeover cam 50 has such a cam surface that, when the cam is rotated by the driving means 7, it reciprocates the piston 29 for one reciprocation for each rotation thereof. When the piston 29 is moved leftward seen in FIG. 1, as the state shown in FIG. 1, the port 12 is connected with the port 13 through the annular passage 18, the port 9 with the port 10 through the annular passage 19, and the port 11 with the port l t through the annular passage 20. To the contrary, when the piston 29 is moved rightward, the port 3 is connected with the port 12 through the annular passage 17, the port 9 with the port 13 through the annular passage 18, the port 111 with the port 14 through the annular passage 19, and the port 11 with the port 15 through the annular passage 211. The cam 30 of the sample drawing means 5 is so adapted as to shift the piston 32 in opposite directions with respect to the piston 29 with a predeten'nined delay angle so that, when the The sample reservoir supporting means 45 shown in FIG. 1 comprises a development suppressing liquid source 36, driving means 37, sample drawing means 38, sample container 39-1, and sample probe 40. In practice, there are prepared a plurality of sample containers for example, as much as 24 containers numbered from 39-1 to 39-24, though the sample container 39-1 is only shown in FIG. 1 for the purpose of simplicity. Furthermore, the sample reservoir supporting means 45 comprises a base plate 41 provided with two sets of port openings a, b and a, b and a rotary plate 42 provided with a plurality of sample reservoirs e e e each being opened to each set of port openings c (1,; c d C24, 11 which are arranged to be faceable with the openings a, b and a, b as the rotary plate is rotated and to establish through passages with the latter through each set of O-rings 0,, O 0 0 0 The sample reservoirs may be made of Teflon tubes, the number of which may be increased or decreased as required. In FIG. 1, there are merely shown the sample reservoirs e and 2 arranged on the sectional line I-O-l in FIG. 2 for the purpose of simplicity. For the same purpose, in FIG. 2, there are merely shown the sample reservoirs e to e In the state shown in FIGS. 1 and 2, the sample reservoirs e, and :2 are respectively cooperating with the ports a, b and a, b. The port a is connected with the development suppressing liquid source 36, and the port b is connected with the port 12 of the changeover means 4. On the other hand, the port b is connected with the sample drawing means 38, and the port a is, in the state shown in FIGS. 1 and 2, connected with the sample container 39-1. The rotary plate 42 is coupled with the driving means 37 to be intermittently rotated around its axis.

The sample introducing system shown in FIGS. 1 and 2 operates as follows:

First, the samples to be separated are gathered in the sample reservoirs e,, e e This operation is performed as follows: First, the sample in the container 39-1 is fed into the sample reservoir e by the drawing action of the sample drawing means 38. Then, the rotary plate 42 is rotated for one step or one twenty-fourth of a revolution in this embodiment, and the sample in the container 39-2 is fed into the sample reservoir e in the same manner. These procedures are repeated for the remaining reservoirs e;,, e.,, e and thus all sample reservoirs are changed with respective samples. In this case, the sample reservoirs are used as a sample measuring means.

In the state of the sample introducing system shown in FIG. 1, let us assume that the developing or eluting solution stored in the source 2 is fed by the pump 35 through the changeover means 4 to the separating column 1, and that, by the drawing action of the sample drawing means 5, the sample stored in the sample reservoir e and the development suppressing liquid in the source 36 have been transferred into the sample reserving means 6. In this condition, if the cam 50 is rotated for a half revolution by a signal indicating the end of the preceding sample analysis, the piston 29 of the flow changeover means 4 is moved rightward, whereby the port 8 is connected with the port 12 through the annular passage 17, the port 9 with the port 13 through the annular passage 18, the port with the port 14 through the annular passage 19, and the port 11 with the port 15 through the annular passage 20. In this condition, therefore, the eluting solution in the source 2 is fed by the pump 35 through the port 10, annular passage 19, port 14, sample reserving means 6, port 13, annular passage 18 and port 9 to the separating column 1, whereby the sample stored in the sample reserving means 6 is pushed out of it by the eluting solution and is introduced into the separating column 1. In this case, the development suppressing liquid which has been introduced into the sample reserving means 6 succeeding the sample and stored therein is in turn introduced into the separating column 1 preceding the sample. As the cam 50 rotates for a half revolution, the cam 30 also rotates for a half revolution, whereby the piston 32 is moved leftward by exhausting the development suppressing liquid through the port 15, and the sample drawing means 5 is restored to the position ready for the next sample drawing operation.

On the other hand, when the piston 29 is moved rightward, the cleaning liquid in the source 3 is passed through the port 8, annular passage 17, port 12, port b, port d sample reservoir e port c and port a to remove the sample materials remaining in these portions by the gravity head of the source 3. After the above-mentioned cleaning process has been finished, the rotary plate 42 is rotated for the one step by the driving means 37, and in place of the ports 0 and d the ports 0 and 11;, come into communication with the ports a and b, respectively.

Then, after the sample and the development suppressing liquid in the sample reserving means 6 have been introduced into the separating column 1, the cams 50 and 30 are further rotated for a half revolution, whereby the piston 29 is moved leftward and restored to the position shown in FIG. 1, or the port 9 is again connected with the port 10 through the annular passage 19, the port 12 with the 'port 13 through the annular passage 18, and the port 14 with the port 11 through the annular passage 20. Therefore, the eluting solution in the source 2 is fed to the separating column 1 by the pump 35 through the port 10, annular passage 19, and port 9. Of course, at this time, the sample is not introduced into the separating column 1.

On the other hand, at an earlier time point in the period of the last-mentioned half revolution of the earns 50 and 30, a passage extending from the sample drawing means 5 to the development suppressing liquid source 36 is established through the port 11, annular passage 20, port 14, sample reserving means 6, port 13, annular passage 18, port 12, port b, port d sample reservoir e port c and port a, whereby as the cam 30 further rotates and the piston 32 is moved rightward toward the position shown in FIG. 1, the sample reserving means 6 is now charged with the sample stored in the sample reservoir e Also in this case, the development suppressing liquid in the source 36 is introduced into the sample reserving means 6 succeeding the sample material in the reservoir e so that the sample is sandwiched by the development suppressing liquid. Here it should be noted that the sample reserving means 6 is so adapted as to have a volume which is, for example, three times that of the sample reservoir. Thus, one complete cycle of operation is accomplished, and the following operation is the repetition of the similar cycles of operation.

The above-mentioned series of operations, except the operation of gathering samples in the sample reservoirs e e e can be performed automatically by applying known technics of automation, such as program systems or timers to the driving means 7 and 37. The development suppressing liquid may be the same liquid as the cleaning liquid. For example, for the samples of amino acids, an acetic acid buffer solution of PH 2.2 may be used as the cleaning liquid.

In the systems for liquid chromatography, the separating column presents a resistance to the flow of liquid, whereby it requires a high pressure of more than 20 kg./cm. to transfer the liquid through the separating column. If such a high pressure is applied to the sample reservoir supporting means 45, the means must be designed to stand the high pressure. Although it is relatively easy to constitute the flow changeover means 4 including the sample reserving means 6 as a pressure structure, it is very difficult to obtain the sample reservoir supporting means 45 wherein a number of O-rings O 0,; O O completely check the leakage of liquid under a high pressure. Even if the sample reservoir supporting means of a pressure structure which is free from any leakage is obtained, it will have a very heavy and complicated structure. Such a problem becomes more serious as the number of sample reservoirs or the O-rings becomes larger. However, the sample introducing system of this invention as shown in FIGS. 1 and 2 is free from the above-mentioned problem, since in this system the sample reservoir supporting means 45 is never subjected to the high pressure.

When the sample is introduced into the separating column, if the development suppressing liquid is not introduced into the column in advance of the sample, the separation of the sample begins before the introduction of the sample is completed, whereby the separability of the sample is very lowered. In the sample, introducing system of this invention, since the development suppressing liquid is introduced into the separating column preceeding the sample, the separation of the sample does not begin before the introduction of the sample into the column is substantially completed. Thus, the lowering of the separability is avoided.

If the samples are remaining in the passage extending from the development suppressing liquid source 36 to the sample reserving means 6, including the sample reservoirs e e e after respective samples were transferred to the sample reserving means, the samples are contaminated by the remaining samples in respective succeeding processes of transferring the samples to the sample reserving means 6, whereby the results of separation include errors. In the system of this invention, however, the above-mentioned errors are avoided by the provision of the cleaning system as already described.

FIGS. 3 and 4 show another embodiment of this invention, wherein the same elements as those shown in FIGS. I and 2 are designated by the same reference numerals. The sample introducing system shown in FIGS. 3 and 4 is different from the system shown in FIGS. l and 2 in the structure of the sample reservoir supporting means. The sample reservoir supporting means 45 in the embodiment of FIGS. 3 and 4 comprises a rotary plate 42 drivingly connected with the drive means 37 and carrying a plurality of sample containers e,, e e, as the sample reservoirs. Therefore, the sample reservoir supporting means 45 of the latter embodiment can be called of an open type, while that of the former embodiment can be called of a closed type. The sample reservoir supporting means of FIGS. 3 and 4 further includes a sample probe as, which can be swung as shown by a broken line as. Since the swinging structures of this kind are well known, details thereof are omitted. The operation of the sample introducing system shown in FIGS. 3 and 4 is identical with that of the system shown in FIGS. I and 2, except that the sample probe 403 is swung to and from the position as shown by M3. Therefore, the explanation of the operation will be omitted.

An advantage of the system shown in FIGS. 3 and 4 is that, since the sample reservoir supporting means 45 is of an open type, the structure of the means is very simple. Since the sample reserving means b can also be used as a sample measuring means, such errors in the amount of the sample materials as caused by the employment of several measuring vessels in conventional method can be avoided and it is always guaranteed that a precisely constant amount of the sample material is introduced into the separating column I.

In the above-mentioned two embodiments of this invention, only one column is used as the separating means. However, if a plurality of separating columns are used with an automatic sample introducing system it will provide a more efficient system for liquid chromatography. As an embodiment of such a system, a sample introducing system for two separating columns is shown in FIG. 5. In FIG. 5, the same elements as those shown in FIG. 3 are designated by the same reference numerals under an additional rule that, as the system of FIG. 5 includes several elements in two parallel lines, the reference numerals for such elements belonging to the first line are attached with and those belonging to the second line are attached with The sample introducing system shown in FIG. 5 operates as follows:

FIG. 3 shows the system in the following conditions:

I. The sample which had been transferred from the sample reservoir 2 to the sample reserving means 6', 6" has been transferred therefrom to the separating columns 1', l" with the flows of the eluting solutions fed by the pumps 35, 35" from the sources 2', 2" through the ports 10', 10", annular pamages 20", ports I4, 14'', sample reserving means 6, s", ports I3, I3, annular passage I9, 19 and ports 9, 9".

2. The probe 46 is swung to the position shown by 46, and the passage extending through the port 12, annular passage I3, port 8, port 12", annular passage 18 and port 8 is cleaned by the flow of the cleaning liquid from the source 3.

3. The piston 32 in the cylinder 31 of the sample drawing means 5 is moved to the right end position seen in FIG. 5 so that a chamber C" defined at the left side of the piston 32 is presenting the largest volume while a chamber C defined at the right side of the piston 32 is presenting the smallest volume.

Then, as the cam 50 is rotated for about one-sixth of a revolution in anticlockwise direction or in the direction indicated by an arrowhead by a signal indicating the end of the preceding sample analysis, the piston 29 is moved rightward seen in FIG. 5, whereby the port 12 is connected with the port 13 through the annular passage I8, the port 9' with the port III through the annular passage 19, and the port 11 with the port 114' through the annular passage 20'. Therefore, the eluting or developing solution in the source 2 is fed by the pump 35 through the port 10, annular passage 19 and port 9' to the separating column I, without passing-through the sample reserving means 6. When the cam 50 is rotated for the above-mentioned one-sixth of a revolution, the cams 50" and 30 are also rotated for the same angle. However, it will be understood that such revolution causes no movement of the pistons 29" and 32.

During the next or second rotation of the cams 50, 50 and 30 of about one-sixth of a revolution, the pistons 29 is kept unmoved at the right end position and the piston 29" is still kept unmoved at the left end position, but the piston rod 33 or the piston 32 is moved leftward seen in FIG. 5, whereby the volume of the chamber C is changed from the minimum to the maximum. At this time, the sample probe 46 is soaked into the sample material in the reservoir e and since the chamber C is in communication with the probe 46 through the port II, annular passage 20', port 14, sample reserving means 6, port 13, annular passage 18 and port 12, the sample in the reservoir e, is transferred to the sample reserving means 6 by the drawing action of the expanding chamber C.

By the next or third rotation of the cams 50, 50 and 30 of about one-sixth of a revolution, whereby the cams are rotated for a half revolution from the starting positions shown in FIG. I, the piston 29 is moved leftward, while the pistons 29" and 32 are still kept unmoved at the left end positions. As the results, the passage extending from the eluting solution source 2' to the separating column 1 through the port 10, annular passage 20, port 14, sample reserving means 6, port 13', annular passage I9 and port 9 is again established, whereby it begins that the sample stored in the sample reserving means 6' is transferred to the separating column I by the flow of the eluting solution pumped by the pump 35.

By the next or fourth rotation of the cams 50, 50" and 30 of about one-sixth of a revolution, the piston 29 is moved rightward, while the pistons 29' and 32 are kept unmoved. Now, the separating column I is connected with the eluting solution source 2" through the port 9", annular passage 19', port Ill" and pump 35", without passing through the sample reserving means 6", whereby the eluting solution in the source 2" is fed to the column l" by the pump 35".

During the next or fifth rotation of the cams 50, 50 and 30 of about one-sixth of a revolution, the piston 32 is moved rightward, while the pistons 29 and 29" are kept unmoved, whereby the chamber C" is expanded to exert the drawing action through the passage extending therefrom to the sample reservoir e through the port Ill", annular passage 20", port 14'', sample reserving means 6", port I3", annular passage 118', port 12'', port 8., annular passage I8 and port 12', whereby the sample in the reservoir e, is transferred to the sample reserving means 6' By the next or sixth rotation of the cams 50', 50 and 30 of about one-sixth of a revolution, the cams being rotated strictly for a revolution as the result, the piston 29" is moved leftward, while the pistons 29 and 32 are kept unmoved and the starting condition as shown in FIG. 1 is restored. At this condition, the passage extending from the cleaning liquid source 3 to the probe, which is now swung to the position 46', through the port 8", annular passage 18", port 12", port 8, annular passage 18, and port 12 is again established, whereby the cleaning of the passage is accomplished.

Although the sample reservoir supporting means 45 used in the sample introducing system shown in H6. is the same one as used in the system shown in FIG. 3, it will be apparent that the sample reservoir supporting means of the closed type shown in H0. 1 may be used in place of the sample reservoir supporting means 45 in FIG. 5.

FIG. 6 shows still another embodiment of this invention, which includes one separating column and a sample reservoir supporting means of the open type, wherein the development suppressing liquid can be introduced into the column prior to the introduction of the sample.

The sample introducing system shown in F IG. 6 comprises a separating column 101, eluting or developing solution source 102, cleaning liquid source 103, flow changeover means 104 and 105, sample drawing means 106, sample reserving means 107 and 108, sample reservoir supporting means 109 of the open type and development suppressing liquid source 163, wherein the sample reserving means 107 has a volume of for example, about three times that of the sample reserving means 100, the latter functioning as a sample measuring means. The flow changeover means 104, 105 and the sample drawing means 106 are respectively cooperated with cams 110, 111 and 112, which are adapted to be simultaneously driven by a driving means 113. The sample drawing means 106 comprises a cylinder 114 and a piston 117 inserted therein to be reciprocated by a piston rod 115, an end of which is resiliently urged against the cam surface of the cam 112 by a spring 116. The inside space of the cylinder 114 is divided into two chambers 118 and 119 by the piston 117. The flow changeover means 104 comprises a cylinder 127 having ports 120 to 126 and a piston 140 inserted in the cylinder and currying O-rings 133 to 138 in sliding contact with the bore of the cylinder so as to define annular passages 128 to 132. The piston 140 is resiliently urged by a spring 139 so that an end thereof always follow the cam surface of the cam 110. In the same manner, the flow changeover means 105 comprises a cylinder 149 havirrg ports 141 to 148 and a piston 162 inserted in the cylinder and carrying O-rings 155 to 160 in sliding contact with the bore of the cylinder so as to define annular passages 150 to 154. The piston 162 is resiliently urged by a spring 161 so that an end thereof always follow the cam surface of the earn 111. The sample reservoir supporting means 109 comprises a driving means 164, a rotary plate 165 adapted to be intennittently driven by the driving means, a plurality of sample reservoirs 166 of the open type arranged with an equal spacing along the circumference of the rotary plate and a sample probe 167 adapted to be soaked in any one of the sample reservoirs 166 or swung to the position shown by 167'. The port 120 is connected with the column 101, the port 121 with the developing solution source 102 through a pump 168, the port 122 with the chamber 118 of the sample drawing means 106, the port 123 with the port 142, the port 124 with the port 125 through the sample reserving means 107, the port 126 with an exhaust pipe, the port 141 with the cleaning liquid source 103, the port 143 with the development suppressing liquid source 163, the port 144 with the chamber 119 of the sample drawing means 106, the port 145 with the sample probe 167, and the port 146 with the port 147 through the sample reserving means 108.

The sample introducing system shown in FIG. 6 operates as follows:

FIG. 6 shows the system in the following conditions:

1. The development suppressing liquid and the sample material which had been stored in the sample reserving means 107 have been or are being fed to the separating column 101 in the above-mentioned order driven by a flow of the eluting solution caused by the pump 168 through the port 121,

annular passage 130, port 125, sample reserving means 107, port 124, annular passage 129 and the port 120.

2. The sample probe 167 is swung to the position shown by 167' and a flow of the cleaning liquid is generated through a passage extending from the clean liquid source 103 through the port 141, annular passage 151 and port 145 to the probe 167 thereby to clean the passage.

Starting from the above-mentioned condition shown in FIG. 6, if the cams 110, 111 and 112 are rotated by the driving means 113 for abut one-fifth of a revolution or 72 in the direction shown by an arrowhead, the piston 162 is moved rightward seen in H6. 6, while the pistons 140 and 117 are kept unmoved, whereby the port 145 is connected with the port 146 through the annular passage 151, the port 142 with the port 143 through the annular passage 152, and the port 147 with the port 144 through the annular passage 153.

By the next or second rotation of the cams 110, 111 and 112 of about 72, the piston 117 is moved leftward seen in FIG. 6, while the pistons 162 and 140 are kept unmoved, whereby the chamber 119 is expanded from the minimum volume to the maximum volume. At this time, the sample probe 167 is already soaked in one of the sample reservoirs 166. Since the passage extending from the probe 167 through the port 145, annular passage 151, port 146, sample reserving means 108, port 147, annular passage 153 and port 144 to the chamber 119 has been established, the sample in the reservoir 166 is transferred to the sample reserving means 108 by the drawing action of the expanding chamber 119.

By the next or third rotation of the cams 110, 111 and 112 of about 72, the pistons 162 and 140 are moved leftward, while the piston 117 is kept unmoved, whereby the port 120 is connected with the port 121 through the annular passage 130, the port 125 with the port 122 through the annular passage 131, the port 141 with the port 145 through the annular passage 151, the port 142 with the port 146 through the annular passage 152, the port 143 with the port 147 through the annular passage 153, and the port 144 with the port 148 through the annular passage 154. The sample probe 167 is swung to the position shown by 167', at this time. Therefore, the passage extending from the cleaning liquid source 103 through the port 141, annular passage 151 and port 145 to the probe 167' is cleaned by the cleaning liquid from the source 103.

By the next or fourth rotation of the cams 110, 111 and 112 of about 72, the piston 117 is moved rightward, while the pistons 162 and 140 are kept unmoved at their left end positions, whereby the chamber 118 is expanded from the minimum volume to the maximum volume. Since the passage extending from the development suppressing liquid source 163 through the port 143, annular passage 153, port 147, sample reserving means 108, port 146, annular passage 152, port 142, port 123, annular passage 129, port 124, sample reserving means 107, port 125, annular passage 131 and port 122 to the chamber 118 has been established the sample which has been stored in the sample reserving means 108 is transferred therefrom to the sample reserving means 107 followed by the development suppressing liquid drawn out from the source 163 by the drawing action of the expanding chamber 118. During this period, on the other hand, the eluting solution is flowing from the source 102 through the port 121, annular passage and port 120 to the separating columm 101 by the action of the pump 168, without passing through the sample reserving means 107.

By the next or fifth rotation of the cams 110, 111 and 112 of about 72, whereby the cams, as a whole, are rotated strictly for a revolution starting from the position shown in FIG. 6, the piston is moved rightward, while the pistons 162 and 117 are kept unmoved, and thus the starting condition as shown in H0. 6 is restored, except that the separating column 101 is now being charged with the next sample to be separated.

Although it is not explained nor illustrated in the drawings, the control of the driving of the earns, the rotary plates of the sample reservoir supporting means and the sample probes will be readily accomplished by employing known arts.

Furthermore, although some particular embodiments of this invention have been described in the above, it is to be understood that many other embodiments can be practiced without departing from the spirit of this invention.

\Ve claimi l. A sample introducing system for use in liquid chromatography, comprising sample separating means, an eluting solution source, means for feeding the eluting solution from said source to said sample separating means, sample reservoir supporting means carrying a plurality of sample reservoirs, sample reserving means having a slender passage, sample drawing means adapted to be intermittently actuated to transfer a sample in one of said sample reservoirs to the slender passage in said sample reserving means, changeover means adapted to be intermittently actuated to feed the eluting solution to said sample separating means through the slender passage in said sample reserving means thereby to intermittently introduce the sample reserved in the slender passage in said sample reserving means tosaid sample separating means and at the same time to interrupt the communication between said sample reserving means and said sample reservoir supporting means, and means for cleaning a passage extending from said sample reservoir supporting means to said sample reserving means while the communication between these two means is interrupted.

' 2. A sample introducing system for use in liquid chromatography, comprising sample separating means, an eluting solution source, means for feeding the eluting solution from said source to said sample separating'means, sample reservoir supporting means carrying a plurality of sample reservoirs, sample reserving means having a slender passage, sample drawing means adapted to be intermittently actuated to transfer a sample in one of sample sample reservoirs to the slender passage in said sample reserving means, changeover means adapted to be intermittently actuated to feed the eluting solution to said sample separating means through the slender passage in said sample reserving means thereby to intermittently introduce the sample reserved in the slender passage in said sample reserving means to said sample separating means and at the same time to interrupt the communication between said sample reserving means and said sample reservoir supporting means, means for cleaning a passage extending from said sample reservoir supporting means to said sample reserving means while the communication between these two means in interrupted, and means for feeding a development suppressing liquid to said sample separating means prior to each introduction of the sample to said sample separating means.

3. A sample introducing system for use in liquid chromatography comprising sample separating means; an eluting solution source; an eluting solution feeding pump; sample reservoir supporting means carrying a plurality of sample reservoirs and adapted to successively bring one of said sample reservoirs into communication with a sample probe; sample reserving means having a slender passage; sample drawing means adapted to perform sequential liquid drawing and exhausting operations; a first passage system extending from said eluting solution source to said sample separating means by way of said eluting solution source to said sample separating means by way of said eluting solution feeding pump; a second e system extending from said sample drawing means to said sample probe by way of the slender passage in said reserving means; a third passage system extending from said eluting solution source to said sample separating means by way of said eluting solution feeding pump and the slender passage in said sample drawing means; a

fourth system extending from said sample drawing means to a drain; and means for changing a first changeover mode at which said first and second passage systems are established and a second changeover mode at which said third and fourth passage systems are established from one of said modes to the other by turns in synchronism with said sample drawing means, wherein at said first changeover mode, eluting solution feeding pump feeds said eluting solution from said eluting solution source to said sample separating means through said first passage system and, in the meantime, said drawing means performs said drawing operation through said second passage system so as to transfer a sample in one of said sample reservoirs into the slender passage in said sample reserving means, and, at said second changeover mode, said eluting solution pump feeds said eluting solution from said eluting solution source to said sample separating means through said third passage system so asto introduce the sample reserved in said slender passage into said sample sample separating means and, in the meantime, said drawing means perfonns said exhausting operation through said fourth passage system so as to exhaust the remaining liquid in said fourth passage system to said drain.

4. A sample introducing system according to claim 3, which comprises means for cleaning a passage extending from said reservoir supporting means to said sample reserving means 'when the communication between these two means in interrupted.

5. A sample introducing system according to claim 4, which comprises means for feeding a development suppressing liquid to said sample separating means prior to each introducing of the sample to said sample separating means, the development suppressing liquid is first transferred from a source thereof to said sample reserving means succeeding the sample by the drawing operation of said sample drawing means thereby to be introduced to said sample separating means preceding the sample when the flow direction is reversed.

6. An apparatus for use in liquid chromatography which comprises a separating means, a flow changeover means and an eluting solution source, means for intermittently conveying said eluting solution from said source, through a portion of the flow changeover means to the separating means, sample reservoir supporting means containing a plurality of sample reservoirs, sample reserving means directly associated with a portion of the flow changeover means, sample drawing means communicating with said sample reserving means through said flow changeover means and adapted to be intermittently actuated to transfer a sample in one of said sample reservoirs to said sample reserving means, through a portion of said flow changeover means, said changeover means being adapted to be intermittently actuated to feed the eluting solution through the changeover means and through the sample reserving means to the sample separating means thereby intermittently introducing the samples reserved in the sample reserving means to said sample separating means and at the same time interrupting the communication between the sample reserving means and the sample reservoir supporting means.

7. The apparatus of claim 6 wherein cleaning means communicate with the passageway extending between the sample reservoir supporting means and the sample reserving means, through the selective operation of the flow changeover means.

8. The apparatus of claim 6 wherein means are provided for producing communication between a development suppressing liquid source and the sample reservoir means.

9. The apparatus of claim 14 wherein the flow changeover means is a cylinder containing a resiliently mounted piston means slidably disposed therein and adapted to be actuated b a driving cam means, said cylinder means being provided wit a plurality of ports and said piston means being provided with a plurality of circumferentially disposed ridges, said ridges and the bore of said cylinder means defining a plurality of fiuidtight annular passages which communicate with said ports, the connection between said ports being controlled by the axial movement of said piston produced by said driving cam means.

10. The apparatus of claim 6 wherein the sample drawing means comprises a cylinder containing a spring loaded piston rod associated with a driving cam means. 7

11. The apparatus of claim 6 wherein the sample reserving means is an elongated conduit means which communicates with two different portions of the flow changeover means.

12. The apparatus of claim 6 wherein the sample reservoir supporting means comprises a rotary plate which contains said plurality of sample reservoirs, each of said sample reservoirs adapted to communicate with a sample container and a sample drawing means for the introduction of the sample into the sample reservoir.

13. The apparatus of claim 12 wherein a driving means is associated with the sample reservoir supporting means.

14. The apparatus of claim 12 wherein the sample reservoirs are elongated conduits in the form of an inverted U-section, each leg of said U-section communicating with the sample container and sample drawing means respectively through the rotary plate of the sample reservoir supporting means.

15. A sample introducing system for use in liquid chromatography, comprising sample separating means, an eluting solution source, means for feeding the eluting solution from said source to said sample separating means, sample reservoir supporting means carrying a plurality of sample reservoirs, sample reserving means, sample drawing means adapted to be intermittently actuated to transfer a sample in one of said sample reservoirs to said sample reserving means, and changeover means adapted to be intermittently actuated to feed the eluting solution to said sample separating means through said sample reserving means thereby to intermittently introduce the sample reserved in said sample reserving means to said sample separating means and at the same time to intercept the communication between said sample reserving means and said sample reservoir supporting means, said changeover means being a cylinder and piston means adapted to be actuated by a driving cam means, said cylinder having a plurality of ports, the connection among said ports being controlled by the axial movement of said piston caused by said driving cam means.

16. A sample introducing system for use in liquid chromatography, comprising sample separating means, an eluting solution source, means for feeding the eluting solution from said source to said sample separating means, sample reservoir supporting means carrying a plurality of sample reservoirs, sample reserving means, sample drawing means adapted to be intermittently actuated to transfer a sample in one of said sample reservoirs to said sample reserving means, said sample drawing means being a cylinder and piston means adapted to be actuated by a driving cam to present an expanding drawing chamber in relation to the operation of said changeover means, and changeover means adapted to be intermittently actuated to feed the eluting solution to said sample separating means through said sample reserving means thereby to intermittently introduce the sample reserved in said sample reserving means to said sample separating means and at the same time to intercept the communication between said sample reserving means and said sample reservoir supporting means. 

2. A sample introducing system for use in liquid chromatography, comprising sample separating means, an eluting solution source, means for feeding the eluting solution from said source to said sample separating means, sample reservoir supporting means carrying a plurality of sample reservoirs, sample reserving means having a slender passage, sample drawing means adapted to be intermittently actuated to transfer a sample in one of sample sample reservoirs to the slender passage in said sample reserving means, changeover means adapted to be intermittently actuated to feed the eluting solution to said sample separating means through the slender passage in said sample reserving means thereby to intermittently introduce the sample reserved in the slender passage in said sample reserving means to said sample separating means and at the same time to interrupt the communication between said sample reserving means and said sample reservoir supporting means, means for cleaning a passage extending from said sample reservoir supporting means to said sample reserving means while the communication between these two means in interrupted, and means for feeding a development suppressing liquid to said sample separating means prior to each introduction of the sample to said sample separating means.
 3. A sample introducing system for use in liquid chromatography comprising sample separating means; an eluting solution source; an eluting solution feeding pump; sample reservoir supporting means carrying a plurality of sample reservoirs and adapted to successively bring one of said sample reservoirs into communication with a sample probe; sample reserving means having a slender passage; sample drawing means adapted to perform sequential liquid drawing and exhausting operations; a first passage system extending from said eluting solution source to said sample separating means by way of said eluting solution source to said sample separating means by way of said eluting solution feeding pump; a second passage system extending from said sample drawing means to said sample probe by way of the slender passage in said reserving means; a third passage system extending from said eluting solution source to said sample separating means by way of said eluting solution feeding pump and the slender passage in said sample drawing means; a fourth passage system extending from said sample drawing means to a drain; and means for changing a first changeover mode at which said first and second passage systems are established and a second changeover mode at which said third and fourth passage systems are established from one of said modes to the other by turns in synchronism with said sample drawing means, wherein at said first changeover mode, said eluting solution feeding pump feeds said eluting solution from said eluting solution source to said sample separating means through said first passage system and, in the meantime, said drawing means performs said drawing operation through said second passage system so as to transfer a sample in one of said sample reservoirs into the slender passage in said sample reserving means, and, at said second changeover mode, said eluting solution pump feeds said eluting solution from said eluting solution source to said sample separating means through said third passage system so as to introduce the sample reserved in said slender passage into said sample sample separating means and, in the meantime, said drawing means performs said exhausting operation through said fourth passage system so as to exhaust the remaining liquid in said fourth passage system to said drain.
 4. A sample introducing system according to claim 3, which comprises means for cleaning a passage extending from said reservoir supporting means to said sample reserving means when the communication between these two means in interrupted.
 5. A sample introducing system according to claim 4, which comprises means for feeding a development suppressing liquid to said sample separating means prior to each introducing of the sample to said sample separating means, the development suppressing liquid is first transferred from a source thereof to said sample reserving means succeeding the sample by the drawing operation of said sample drawing means thereby to be introduced to said sample separating means preceding the sample when the flow direction is reversed.
 6. An apparatus for use in liquid chromatography which comprises a separating means, a flow changeover means and an eluting solution source, means for intermittently conveying said eluting solution from said source, through a portion of the flow changeover means to the separating means, sample reservoir supporting means containing a plurality of sample reservoirs, sample reserving means directly associated with a portion of the flow changeover means, sample drawing means communicating with said sample reserving means through said flow changeover means and adapted to be intermittently actuated to transfer a sample in one of said sample reservoirs to said sample reserving means, through a portion of said flow changeover means, said changeover means being adapted to be intermittently actuated to feed the eluting solution through the changeover means and through the sample reserving means to the sample separating means thereby intermittently introducing the samples reserved in the sample reserving means to said sample separating means and at the same time interrupting the communication between the sample reserving means and the sample reservoir supporting means.
 7. The apparatus of claim 6 wherein cleaning means communicate with the passageway extending between the sample reservoir supporting means and the sample reserving means, through the selective operation of the flow changeover means.
 8. The apparatus of claim 6 wherein means are provided for producing communication between a development suppressing liquid source and the sample reservoir means.
 9. The apparatus of claim 14 wherein the flow changeover means is a cylinder containing a resiliently mounted piston means slidably disposed therein and adapted to be actuated by a driving cam means, said cylinder means being provided with a plurality of ports and said piston means being provided with a plurality of circumferentially disposed ridges, said ridges and the bore of said cylinder means defining a plurality of fluidtight annular passages which communicate with said ports, the connection between said ports being controlled by the axial movement of said piston produced by said driving cam means.
 10. The apparatus of claim 6 wherein the sample drawing means comprises a cylinder containing a spRing loaded piston rod associated with a driving cam means.
 11. The apparatus of claim 6 wherein the sample reserving means is an elongated conduit means which communicates with two different portions of the flow changeover means.
 12. The apparatus of claim 6 wherein the sample reservoir supporting means comprises a rotary plate which contains said plurality of sample reservoirs, each of said sample reservoirs adapted to communicate with a sample container and a sample drawing means for the introduction of the sample into the sample reservoir.
 13. The apparatus of claim 12 wherein a driving means is associated with the sample reservoir supporting means.
 14. The apparatus of claim 12 wherein the sample reservoirs are elongated conduits in the form of an inverted U-section, each leg of said U-section communicating with the sample container and sample drawing means respectively through the rotary plate of the sample reservoir supporting means.
 15. A sample introducing system for use in liquid chromatography, comprising sample separating means, an eluting solution source, means for feeding the eluting solution from said source to said sample separating means, sample reservoir supporting means carrying a plurality of sample reservoirs, sample reserving means, sample drawing means adapted to be intermittently actuated to transfer a sample in one of said sample reservoirs to said sample reserving means, and changeover means adapted to be intermittently actuated to feed the eluting solution to said sample separating means through said sample reserving means thereby to intermittently introduce the sample reserved in said sample reserving means to said sample separating means and at the same time to intercept the communication between said sample reserving means and said sample reservoir supporting means, said changeover means being a cylinder and piston means adapted to be actuated by a driving cam means, said cylinder having a plurality of ports, the connection among said ports being controlled by the axial movement of said piston caused by said driving cam means.
 16. A sample introducing system for use in liquid chromatography, comprising sample separating means, an eluting solution source, means for feeding the eluting solution from said source to said sample separating means, sample reservoir supporting means carrying a plurality of sample reservoirs, sample reserving means, sample drawing means adapted to be intermittently actuated to transfer a sample in one of said sample reservoirs to said sample reserving means, said sample drawing means being a cylinder and piston means adapted to be actuated by a driving cam to present an expanding drawing chamber in relation to the operation of said changeover means, and changeover means adapted to be intermittently actuated to feed the eluting solution to said sample separating means through said sample reserving means thereby to intermittently introduce the sample reserved in said sample reserving means to said sample separating means and at the same time to intercept the communication between said sample reserving means and said sample reservoir supporting means. 